218997117 has 12 divisors (see below), whose sum is σ = 324879100. Its totient is φ = 142051968.

The previous prime is 218997089. The next prime is 218997127. The reversal of 218997117 is 711799812.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 204089796 + 14907321 = 14286^2 + 3861^2 .

It is not a de Polignac number, because 218997117 - 2¹⁵ = 218964349 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218997127) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 328492 + ... + 329157.

Almost surely, 2^218997117 is an apocalyptic number.

It is an amenable number.

218997117 is a deficient number, since it is larger than the sum of its proper divisors (105881983).

218997117 is a wasteful number, since it uses less digits than its factorization.

218997117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 657692 (or 657689 counting only the distinct ones).

The product of its digits is 63504, while the sum is 45.

The square root of 218997117 is about 14798.5511790851. The cubic root of 218997117 is about 602.7623709934.

The spelling of 218997117 in words is "two hundred eighteen million, nine hundred ninety-seven thousand, one hundred seventeen".